Agmt 2006 State Coastal Conservancy

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tit .. PROJECT NAME - - CalEP A's Department of Pesticide Regulation (DPR) for registration and is expected to be approved for eSt\1arine use in early summer 2005. The ISP would like to include the use of imazapyr in the Control Program because under certain estuarine conditions it has several apparent benefits over the use of glyphosate (including increased efficacy and fewer limitations on timing of application). Additionally, because of the exvemely rapid spread of invasive cord grasses since the 2003. approval of the SCP, imazapyr may be used on a cumulatively -larger area than that originally envisioned in the 2003 FPElR. .... . Since the FEIS/R did not analyze the -potential effects of using imazapyr and associated surfactants and colorants, and the extent of its _ use, these changes in the proj ect and their potential environmental effects must be analyzed under CEQA. The CEQA Guidelines specify the process for doing so under Guidleines Sections 15164(8) and 15162. Section 15164(a) of the Guidelines specify thai the an "addendum" to a previously certified ElR, without the need for further environmental review, if some changes or additions to a proj ect _ are -necessary, but none of the conditions described in Guidelines Section 15162 calling for preparation of a-subsequent EIR have occurred. According to Section 15162, a s~bsequent EIR shall not be prepared for the . revised project unless the Conservancy determines, based on substantial evidence in light of the whole record, that the change in the project will result in new significant effects not previously considered in the FEIS/R or will result in a substantial increase in the environmental effects previously considered. In order to answer the question of whether the use ofimazapyr and associated surfactant~and colorants over an expandedtreatrilent area would trigger new or increased environmental effeCts, the Conservancy commissioned a detailed evaluation of the use of this herbicide in th~ San Francisco Estuary by Leson & Associates in May 2005 (Appendix D to Exhibit 5 of this staff recommendation), including a review of existing ecological risk assessments for use ofimazapyr in estuarine and forestry applications, and a comprehensive literature search and review of publications on ecological impacts, toxicity, and fate and transport of imazapyi and its formulations including adjuvants that could potentially be used with imazapyr. From its review of existing scientific data, the Leson & Associates Report concluded that the use of imazapyr alui-..-:- associated surfactants and colorants: would not result in material impacts to estuarine environments or on water quality, because of its rapid degradation and dilution by incoming tides; would not pose significant toxicity concerns for fish, birds or aquatic organisms; would not pose any increased risk to hllJ!1an health and safety; and would pose less effects on the environment than glyphosate because imazapyr and its surfactants are less toxic and imazapyr degrades more readily. The report also noted that in imazapyr has been shown to be a more effective herbicide in treating invasive Spartina." This may result in the need for fewer herbicide applications, but may alsO' increase adverse effects on non-target plants in the event of drift or overspray. . Based on these conclusions, Conservancy staff determined that an Addendum to the FEISIR, rather than a subsequent ElR, was the appropriate vehicle under CEQA to- document the change in the ISP Control Program. The proposed Addendum, which is attached as Exhibit 5, details the change to the ISP Control Program associated with the incorporation of imazapyr as an herbicide and details the basis for the conclusion that this change will not result in new or increased significant environmental effects. In brief, that conclusion, which is fully supported by the n 1A r.,~